1. Field of the Invention
The present invention relates to a tank rubber cushion for providing a vibration-damping support of a fuel tank against a vehicular body.
2. Description of the Related Art
Tank rubber cushions have conventionally been used in order to let a fuel tank be supported by the vehicular body. One such example is the one described in U.S. Publication No. US 2009/0077785.
Meanwhile, a tank rubber cushion is required to have a vibration-damping performance so as to achieve stable supplies of fuel into the tank and reduce transmission of vibration to the vehicular body caused by a displacement of the fuel tank, and is also required to attenuate flow noise within the fuel tank. In order to meet these requirements, it is considered effective for a tank rubber cushion to sustain enough rigidity of the support spring in the vertical direction, and at the same time, to be provided with low spring characteristics in the horizontal direction.
However, the tank rubber cushion of conventional structure described in US 2009/0077785 utilizes the spring characteristics associated with compression deformation of a rubber elastic body in both vertical and horizontal directions, although the spring characteristics are adjusted by the provision of elastic protrusions. Therefore, it was difficult for the tank rubber cushion of US 2009/0077785 to meet the intended spring characteristics in either vertical or horizontal direction.